1. Field of the Invention
The present invention relates to an antenna, and more particularly to a built-in multi-band antenna adapted for being used in a portable mobile communication device.
2. The Related Art
Nowadays, mobile communication technology has been developed faster and faster, and portable mobile communication devices have been developed towards a multifunctional and miniaturized direction. For example, the portable mobile communication device, such as a cell phone and a notebook, has been developed with a GPS (Global Positioning System) navigation function and a wireless connection function. In order to realize the GPS navigation function and the wireless connection function, the portable mobile communication device need operate in GPS (Global Positioning System) and WIFI (Wireless Fidelity) frequency bands. Accordingly, an antenna for receiving and transmitting GPS signals and another antenna for receiving and transmitting WIFI signals are needed to be used in the portable mobile communication device.
However, when the two antennas are both located in the portable mobile communication device, they will occupy a larger space in the portable mobile communication device that makes the portable mobile communication device have a larger volume, and further increases a manufacture cost of the portable mobile communication device. In order to ensure the portable mobile communication device can operate in GPS (Global Positioning System) and WIFI (Wireless Fidelity) frequency bands, and simultaneously, ensure the portable mobile communication device has a smaller volume, a built-in multi-band antenna with a smaller volume need be designed for receiving and transmitting GPS and WIFI signals.